Nano-scale engineering of surfaces - Functionalized nanoparticles as versatile tools for the introduction of biomimetics on surfaces

Historically, advances in materials synthesis and processing have been pivotal in the emergence of advanced medical technologies. Tissue Engineering (TE) and other organ regenerative techniques depend on the creation of a mechanically well-defined environment (scaffold) that is rich in biomolecular signals to achieve its objectives, namely the growth of functional neo-tissue. The evolution of neo-tissue is governed by material-cellular interactions, which in turn are dictated by surface characteristics such as texture and chemical functionality. To enable predictive outcomes in TE, polymeric fibers and cellular solid scaffolds should be engineered to include the presentation of biomolecular signals. Since information that is introduced on the material surface is processed as biomechanical and biochemical signals through receptors, which are nano-meter sized entities on cell surfaces, it is therefore important that this information be presented on the same length scale as it occurs in nature. A robust, reproducible and simple way to assembly physical and biochemical information therefore needs to be developed. We hypothesized that an assembly of functionalized particles could serve as a versatile tool for imparting texture and chemical functionality on a variety of surfaces. We further hypothesized that nano-scale resolution of physical and chemical information can be achieved using functionalized nanoparticles (FNP) as building blocks. Pre-functionalization allows for the precise control over density and spatial distribution of information on the surface. Using functionalized inorganic oxides; surfaces of hard (stainless steel and titanium) and soft (polyurethane) substrates have been modified so as to impart reproducible texture and chemically derivatizable functionality. These surface modification coatings can be tuned to possess tethered or covalently adsorbed biomolecules such as peptides, growth factors and proteins and can serve as a platform for engineering biomimetic interfaces to modulate cellular behavior toward implants and in scaffolds for TE.